Hopper car having double-curved side walls

ABSTRACT

A hopper car having double-curved side walls for transporting bulk solids. The car has side walls, end walls, and a bottom which are all joined to present a container for transporting the bulk solids. The bottom presents at least one opening for discharge of the bulk solid. Each side wall presents upper and lower convex sections forming an indentation at approximately the vertical center of the side wall.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related in general to a hopper car for transporting bulk solids and more particularly to a hopper car with double-curved side walls for increasing the cargo carrying volume.

2. Description of Related Art

Hopper cars are commonly used to transport and sometimes store bulk materials. Hopper cars are typically constructed from a series of joined hoppers having side walls and end walls. A typical hopper car side wall is convex with an apex at the wall's vertical center. Each hopper has a bottom surface with a discharge opening in order to discharge the cargo. A gate is coupled to each hopper bottom to control the cargo discharge through the opening. Depending on the type of cargo, the hopper car may have a cover.

The dimensions of hopper cars must conform with industry standard clearance dimensions. For railroad hopper cars, the Association of American Railroads (AAR) establishes maximum clearance dimensions for all rail cars including hopper cars. For over-the-road trucks, the Federal Highway Administration and state agencies establish maximum dimensions. These maximum dimensions ensure that a hopper car will not strike objects positioned outside of the clearance zone.

One way to increase the volume that a hopper car may carry without exceeding maximum height and width clearance dimensions is to lengthen the car. However, lengthening the distance between the trucks or wheels of a hopper car creates a problem when the car travels around curved portions of track or road. If the distance between the trucks or wheels is lengthened too much, then the car's midsection will extend outside of the clearance zone for the curved portion. One solution to this clearance problem is to correlate the distance between the trucks or wheels of the car with the width at the car's midsection such that the car does not extend outside of its clearance zone. One way to achieve this correlation is to form concave portions in a car's side walls such that the width of the car's midsection is reduced. However, in a typical hopper car with convex side walls, forming such a concave portion weakens the side walls such that they might fail when subjected to the forces of carrying cargo.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed toward a hopper car for transporting bulk solids. The hopper car has opposed generally upright side walls, opposed generally upright end walls joined to each side wall, and a bottom joined with each side and end wall.

Each side wall presents upper and lower convex sections which form an indentation at approximately the vertical center of the wall. The upper and lower convex sections increase the cargo carrying capacity of the hopper car. The bottom of the car presents at least one opening for discharge of the bulk solid carried within the car.

In another embodiment, each side wall includes a concave portion which extends in a longitudinal direction to reduce the width of the car's midsection. This width reduction provides additional clearance on curved portions of track, ensuring that the side walls do not extend over established clearance lines. The upper and lower convex sections enhance the rigidity of the side walls to counteract any weakening created by forming the concave portions.

Additional aspects of the invention, together with the advantages and novel features appurtenant thereto, will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned from the practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view, with portions broken away, of one embodiment according to the present invention of a hopper car having double-curved side walls;

FIG. 2 is a cross-sectional view of the hopper car of FIG. 1;

FIG. 3 is a perspective view of an alternative embodiment of the hopper car according to the present invention showing a reduced width at the car's midsection; and

FIG. 4 is a top plan view of the car of FIG. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

A railroad hopper car 10 for transporting bulk solids is depicted in FIG. 1. The hopper car has a frame 12, a container 14 mounted to the frame and truck assemblies 16 mounted to each end of the frame. As depicted in FIGS. 1 and 2, container 14 has opposed generally upright side walls 18, opposed generally upright end walls 20 joined to each side wall, a horizontal discontinuous bottom 22 joined with each side and end wall, inverted v-shaped structures 24 joined with the bottom and each side wall, and a convex cover 25 joined to each side and end wall. Side walls 18 extend in a longitudinal direction of the car between end walls 20.

As depicted in FIGS. 1 and 2, each side wall 18 presents an upper convex section 26, a lower convex section 28, and discharge sections 30 a-b and 32 a-b. As depicted in FIG. 1, bottom 22 has two end openings 34 a-b and two intermediate openings 36 a-b for discharge of the bulk solid. Each discharge section 30 a-b and 32 a-b extends down from lower section 28 and joins with bottom 22 adjacent one of openings 34 a-b and 36 a-b. Inverted v-shaped structures 24 are located between adjacent openings 34 a-b and 36 a-b. As depicted in FIG. 2, a discharge gate 38 is coupled with bottom 22 adjacent opening 34 a for regulating discharge of the bulk solid through the opening. It is understood that the bottom is adapted to have gates coupled with it adjacent openings 34 b and 36 a-b as well.

As depicted in FIG. 2, convex sections 26 and 28 form an indentation 29 at approximately the vertical center of each side wall 18. Convex sections 26 and 28 have approximately equal curvature. Cover 25 also has approximately equal curvature to convex sections 26 and 28. The radius of curvature of the cover and convex sections is approximately 105 inches in the preferred embodiment, and can range from 95 to 120 inches. The convex sections increase the cargo carrying capacity of the hopper car over that of a typical hopper car having convex side walls with one apex. The sections also enhance the wall's rigidity such that it can withstand the forces resulting from the increased cargo within the car.

As shown in FIGS. 1 and 2, frame 12 presents first, second and third reinforcing members 40, 42 and 44 joined to each side wall 18. First reinforcing member 40 is joined to each side wall 18 extending along the top of the wall. Second reinforcing member 42 is joined to each side wall 18 extending along indentation 29. Third reinforcing member 44 is joined to each side wall 18 extending along the base of lower section 28.

FIGS. 3 and 4 depict an alternative embodiment of a hopper car 110 according to the present invention. Car 110 is substantially identical to car 10 described above in connection with the embodiment depicted in FIGS. 1 and 2 except that car 110 has side walls 118 which each include a concave portion 162 extending in a longitudinal direction of the car. Each side wall 118 has a first end portion 160 a joined with an end wall 120 and a second end portion 160 b joined with the opposite end wall 120. Concave portion 162 extends in a longitudinal direction between first and second end portions 160 a and 160 b. Concave portion 162 reduces the width of car 110 in its midsection. For the rail car depicted, this width reduction provides additional clearance on curved portions of track.

As depicted in FIG. 3, first end portion 160 a has upper and lower convex sections 126 a and 128 a. Likewise, second end portion 160 b has upper and lower convex sections 126 b and 128 b. The upper and lower convex sections enhance the rigidity of side wall 118 to counteract any weakening created by forming the concave portion 162. Concave portion 162 permits lengthening car 110 while still conforming with industry standard clearance requirements for curved portions of track. Convex sections 126 a and 128 a form an indentation 129 a at approximately the vertical center of side wall 118, and likewise convex sections 126 b and 128 b form an indentation 129 b.

From the foregoing it will be seen that this invention is one well adapted to attain all ends and objectives herein-above set forth, together with the other advantages which are obvious and which are inherent to the invention. The hopper car of the present invention has an increased cargo carrying capacity because its side walls have upper and lower convex sections. Additionally, the upper and lower convex sections counteract weakening due to the formation of a concave portion in the side wall's midsection. This concave portion permits lengthening the car to increase volumetric capacity, while still conforming with industry standard clearance requirements for curved portions of track.

Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative, and not in a limiting sense. Although, car 10 depicted in FIG. 1 is shown with four openings and car 110 depicted in FIG. 3 is shown with five openings, it is understood that either car may have any number of openings. Each side wall of the present invention may be formed from one sheet of material, or in the alternative the wall may be formed from different sheets of material which are joined with welds, fasteners, or any other means known in the art. Likewise, the container walls may be joined by welds, fasteners, or any means known in the art, and the frame may be joined to the container by welds, fasteners, or any means known in the art.

While specific embodiments have been shown and discussed, various modifications may of course be made, and the invention is not limited to the specific forms or arrangement of parts and steps described herein, except insofar as such limitations are included in the following claims. Further, it will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 

1. A hopper car for transporting bulk solids, said car comprising: opposed generally upright side walls each presenting upper and lower convex sections forming an indentation at approximately the vertical center of said side wall; opposed generally upright end walls joined to each of said side walls; and a bottom joined with each of said side walls and each of said end walls, said bottom presenting an opening for discharge of the bulk solid.
 2. The car of claim 1, wherein each of said side walls includes a concave portion extending in a longitudinal direction to reduce the width of said car in its midsection thereby providing additional clearance on curved portions of track.
 3. The car of claim 2, wherein each of said side walls includes first and second end portions each joined with one of said end walls, wherein said concave portion extends between said first and second end portions, and wherein each of said first and second end portions presents upper and lower convex sections forming an indentation at approximately the vertical center of said side wall.
 4. The car of claim 1, wherein said convex sections have approximately equal curvature.
 5. The car of claim 4, wherein the radius of curvature of said convex sections is between 95 to 120 inches.
 6. The car of claim 1, further comprising a convex cover joined to said side and end walls.
 7. The car of claim 6, wherein said cover and convex sections have approximately equal curvature.
 8. The car of claim 7, wherein the radius of curvature of said cover and convex sections is between 95 to 120 inches.
 9. The car of claim 1, further comprising a first reinforcing member joined to each side wall extending along approximately the top of said wall, a second reinforcing member joined to each side wall extending along said indentation, and a third reinforcing member joined to each side wall extending along approximately the base of said lower section.
 10. The car of claim 1, wherein said bottom presents a plurality of openings for discharge of the bulk solid, each side wall presents a plurality of discharge sections corresponding with said openings, each discharge section extends down from said lower section and joins with said bottom adjacent one of said openings, and said car further comprises inverted V-shaped structures joined with said bottom between adjacent openings.
 11. The car of claim 1, further comprising a discharge gate coupled with said bottom adjacent said opening for regulating discharge of the bulk solid through said opening. 